Just returned from Buenos Aires. We stayed at the Park Tower for 5 nights in Dec 2007-Jan2nd. It has a nice lobby that smells divine when you walk in.

The rooms are nice but the service there sucks! They claim to be a 5 star but the service levels are awful! You'd expect the concierge service to be excellent when you stay at a hotel that claims to be a St.Regis. This was pathetic. The concierge hardly ever picked up the phone, it was typically the bellman taking the phone.

Even if they did they really did not help nor did they know too many things. They are lackadaisical or complacent. I cant put my finger on it.

On the other hand we stayed 3 nights at the marriott just a block up from there on Plaza San Martin. It is a historic hotel but still charming. I admit the Marriott rooms are smaller and bathrooms small as well (some would say charming) but the service was superlative. The concierge was excellent. They suggested some of the best bars/restaurants we could have ever gone to.

As far as location goes, the Marriott is right on Calle Florida which has tons of shopping! There are all kinds of leather stores Florida and other fancy shopping as well. Watch out those leather salesmen are very persuasive!

You are 15-20 minutes walking distance to Plaza de Mayo, Casa Rosada and other site. Also a brisk 25-30 minute walk to Recoletta cemetary.

Recoletta is where all the high-end homes and shopping is and may actually be a more central to all the things to do in Buenos Aires.

From either the Marriott or the Park Tower you are 15 minutes to Puerto Madeiro which has a long row of restaurants on the water. This is where we spent new years! It was fantastic. The food is good at the Parillas and the Italian Restaurants (Bice)

We particularly loved this restaurant/bar called Milion. (I think it is in the Montevideo) http://www.milion.com.ar/eng/index.html
Do check it out! It is a wonderful restaurant/bar that has 3 storeys. Outdoor seating, balcony seating, and all kinds of other seating. This where a lot of BA crowd hangs out out until 3 am.
The other ones we loved were Gran Danzon. This is a fantastic restaurant as well!

Palermo Soho is about a 20 minute cab ride from the Park/Marriot and this where some of the best bars and restaurants are.
Bar Uriarte is a favorite of mine! It is an excellent restaurant/lounge/bar. Fantastic vibe.

Also do go to Casa Cruz. It is probably the best food we had in BA. You certainly do need reservations to get in there.

One more thing though. You should certainly visit Tigre, take the tren de la costa up and cruise down the river delta back to BA. It is a great short trip.
Shop for handicrafts in the Tigre. The prices are much better.

Although staying at the Park Tower is a bit high 280-375, you can negotiate in low seasons. The best part is that you get your own butler; the rooms are a great size. Shower is fantastic that you have a hard time getting out.

However, the greatest part about staying in this hotel is the concierge. The service is fantastic with show recommendation, to restaurants and shopping. If you have something in mine but not sure what it is...no problem, just explain what you need from your room and they will find it and call you back. Then they will have a cab waiting for you and he will already know where you are going.

I love staying here and my favorite person from concierge is Julian. Just ask by name and he will call you back.

My husband and I travel a lot and we like to stay at nice hotels. We just returned from Buenos Aires and stayed at both Marriott Plaza Hotel and at Sheraton Park Tower (St Regis). We opted to stay at Park Tower over New Years for 5 nights over the Marriott since it was luxury collection of SPG and my husband is a platinum member.
We were given a very low floor room even though we registered as SPG Elite members and on asking for a better room we were informed ' this is a luxury hotel you will find all rooms to be good rooms'. Room was fine though.
We had informed at check in we were extending a night and nobody even bothered with that so we had to do the extension online.
We were refused breakfast even though the table was laden with food because it was 10:50 and breakfast ended at 11:00. And unfortunatley it was not even done graciously instead with a big scowl we were told there is no breakfast. We just walked away.
On our last evening we were locked out of our room and when we went down to speak to the only person available he was busy chatting on his cell phone for 10-15 mins before even acknowledging us eventually when we informed him that we were locked out he said he thought we were supposed to be out of the hotel by now. We informed him about the extension which he located online and told us we should have let them know...which we had on checking in....he just barely apologized and then got back on the call he was on promptly.
The concierge service was non existent. Most times the bell boy was answering.
Unfortunatley in trying to go more luxury we missed out staying at Marriott longer which had MUCH better service and concierge.

Outstanding service in this remarkably exciting city. Terrific restaurants and hot nightlife within a 10-15 minute walk. Hit the Alamo Bar if youre interested in watching US sports; it's an expat hangout. Kilkenny's is another fun spot.

You *must* walk down Calle Florida while you're in BA.

The hotel itself is simply one of the best. Friendly, professional service, sumptuously appointed rooms, and an interesting lobby bar. I've traveled ~40 nights/yr. for more than a decade, and the Park Tower is definitely worth the preimum you pay. The attached Sheraton is ok, too, but I'd not trcommend the Sheraton Libradores (sp).